2x + 2y =80 2x + 5y = 100

Penjelasan dengan langkah-langkah:

2x = 80 – 2y >> x = 40 – y

2x + 5y = 100

80-2y + 5y = 100

3y = 20

y = 20/3

x = 40 – y

x = 40 – 20/3

x = 120/3 – 20/3

x = 100/3

Jawabannya adalah x = 100/3 dan y = 20/3. Karena:

• 2x + 2y = 80

• 2 . 100/3 + 2 . 20/3 = 80

• 200/3 + 40/3 = 80

• 240/3 = 80

• 240 ÷ 3 = 80

• 2x + 5y = 100

• 2 . 100/3 + 5 . 20/3 = 100

• 200/3 + 100/3 = 100

• 300/3 = 100

• 300 ÷ 3 = 100